Some nutrients are key for the development of the nervous and immune systems, so supplementation is likely to be recommended to individuals with suboptimal levels. While the pills are critical for correcting nutritional insufficiencies, their safety hinges greatly on their dosage. At larger doses, vitamin B6 supplements have been linked to irreversible nerve damage.
Vitamin B6 is critical for the functioning of a number of processes in the brain, including the regulation of sugar, fat and protein.
It is also a key nutrient used in the development of the skin and nerves, making it indispensable to good health.
The Harvard T.H Chan School of Public Health states: “Vitamin B6, or pyridoxine, is a water-soluble vitamin found naturally in many foods, as well as added to foods and supplements.
“[It] has been widely studied for its role in disease prevention. The vitamin in supplement form shows the most promise for the treatment of pregnancy-induced nausea, but such use should only occur under the supervision of a physician.
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“Adequate blood levels of B6 may be associated with lower risk of cancers, compared to low blood levels.”
While most people get enough vitamin B6 from their diet, those who are deficient in the nutrient may turn to supplementation to correct their insufficiencies.
Individuals with an underlying deficiency in vitamin B12 are more likely to be deficient in vitamin B6.
Short-term treatment with vitamin B6 supplements are generally deemed safe, but at higher doses, they could pose substantial health risks.
Studies state that toxicity from vitamin B6 mimics those of a vitamin B6 deficiency; with both cases resulting in nerve damage.
The presentation for toxicity from vitamin B6 is peripheral sensory neuropathy.
Peripheral sensory neuropathy results from damage to the nerves located outside of the brain and spinal cord.
This can cause weakness, numbness and pain, with symptoms usually concentrated in the hands and feet, where the nerves are more sensitive to touch.
But the condition can also affect other areas and biological functions, such as digestion, urination and circulation.
Neuropathy from massive exposures can cause long-term disability or death.
The Committee on Toxicity explains: “In most instances, the clinical signs of toxicity were reversible once ingestion of high doses of vitamin B6 has ceased.
“However, in some instances where doses of this vitamin were especially high, signs of damage remained.”
Other symptoms linked to the overconsumption of vitamin B6 include a lack of muscle control, and painful, disfiguring skin lesions.
It should be noted that toxicity occurs only when vitamin B6 is taken as a supplement, so dietary sources do not pose the same risk.
The nutrients can naturally be found in eggs, legumes and cereals, with some rich sources including fish, beef liver, and other organ meats.